The fossils of a few organisms are shown below. the first image is a bird, the second image is a dinosaur, and the third image is an archaeopteryx. the dinosaur fossils were obtained from the lower sedimentary layer, and archaeopteryx was found above it. the fossils of the bird were found on the topmost layer, which suggests that they’re the . this information also suggests that archaeopteryx .

blue

light-years

magnitude

b is the correct answer

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.